Accomodative micropsia, a phenomenon in which an object of fixed angular size looks smaller when the eyes are adjusted for near vision than when they are adjusted for distance vision is under study. The phenomenon has been found to correlate more closely with the convergence of the eyes than with accommodation. An ongoing study of its distribution within the visual field shows that the effect is greatest in the fovea and decreases rapidly with retinal eccentricity. Determination of the time course of the perceptual phenomenon is being undertaken to learn if perceived size starts to change before or after the onset of a convergence movement. Measurements of the preceived size of a briefly presented test target will be assessed in light of when, with respect to a convergence movement, the target was presented. Electro-oculograms will be used to record convergence. BIBLIOGRAPHIC REFERENCES: HOLLINS, M. (1974). Does the central human retina stretch during accommodation? Nature, 25l, 729-730.